Notes
Washington State Department of Ecology and Public Health – Seattle & King County report on arsenic and lead soil contamination study covering 200 square miles of mainland southern King County. Study findings from 75 sample locations link contamination to the former Asarco smelter in Ruston, with highest levels on Vashon and Maury Island (up to 460 ppm arsenic, 1,300 ppm lead). Contamination follows prevailing Puget Sound wind patterns northeast from the Ruston smelter site. Identifies Tacoma Smelter Plume as source; outlines Ecology next steps including Pierce County sampling, property sampling guidance under Washington’s Model Toxic Control Act (MTCA), and legal action against Asarco under Washington’s Model Toxic Control Act.